Mairéad MacSweeney

Reading is central to academic and vocational success. Some deaf children face reading challenges due to limited access to spoken or signed language. Robust phonological representations are key to reading development in hearing children. Spoken language phonology may be one of many contributors to reading development in deaf children. Indeed, speechreading ability correlates with reading skill in both deaf and hearing individuals, suggesting it is linked to reading development regardless of hearing status. Further support for this hypothesis would be provided by evidence that similar neural representations of speech phonology are evoked by visual speech and other language forms (auditory speech and text) and that these neural representations are related to reading proficiency. We used fMRI and representational similarity analysis (RSA) to identify shared neural representations of spoken language phonological structure. A group of deaf adult participants (N = 22), with a mixture of sign language and spoken language backgrounds and reading abilities, were presented with single lexical items as visual speech and dynamic text (cursive text, revealed letter-by-letter to promote a phonological reading strategy). Adult hearing participants (N = 25) were presented with the same words, but as visual speech and auditory speech. Shared neural representations of phonological structure of English words were found in each group in the superior and middle temporal cortex (STC/MTC) and these abstract representations were more similar across different language forms in better readers. Our data provide neurobiological evidence of the contribution of visual speech to abstract phonological representations of spoken language, that relate to reading proficiency, in both deaf and hearing adults.

Bilinguals show differences in face processing compared to monolinguals, automatically orienting more rapidly to faces and dwelling longer on faces and mouths than monolinguals. However, it is difficult to identify specific visual strategies from average‐level data. This pre‐registered study uses growth curve analysis within trials to explore individual differences in monolingual and bilingual children's dynamic allocation of visual attention to static faces (“Face Pop‐Out”) and dynamic mouths (“50 Faces”). Participants were from Greater London in two age groups: 7‐ to 18‐month‐olds ( n = 131) collected at the Birkbeck Babylab, and 18‐ to 34‐month‐olds ( n = 745) whose data was publicly available from the Developing Human Connectome Project. Results show that children's attentional trajectories for viewing faces and mouths are sensitive to age and early language environment. Specifically, young bilinguals showed stronger systematic disengagement than monolinguals from faces and mouths after initial orientation. Older bilinguals prioritized the mouth more than monolinguals, driven by a steeper increase in mouth‐looking over stimulus time. Age‐dependent shifts in attentional allocation over stimulus time were evident within both age groups, particularly in static face viewing. In infants, younger children showed earlier re‐fixations to static faces than older children. In toddlers, attention to faces was more stable over stimulus time in older than younger children. Overall, results suggest that age and early exposure to two languages modulates the temporal structure of children's social attention from 7‐ to 34‐months of age.

Reading is central to academic and vocational success. Some deaf children face reading challenges due to limited access to spoken or signed language. Robust phonological representations are key to reading development in hearing children. Spoken language phonology may be one of many contributors to reading development in deaf children. Indeed, speechreading ability correlates with reading skill in both deaf and hearing individuals, suggesting it is linked to reading development regardless of hearing status. Further support for this hypothesis would be provided by evidence that similar neural representations of speech phonology are evoked by visual speech and other language forms (auditory speech and text), and that these neural representations are related to reading proficiency. We used fMRI and Representational Similarity Analysis (RSA) to identify shared neural representations of spoken language phonological structure. A group of deaf adult participants (N=22), with a mixture of sign language and spoken language backgrounds and reading abilities, were presented with single lexical items as visual speech and dynamic text (cursive text, revealed letter-by-letter to promote a phonological reading strategy). Adult hearing participants (N=25) were presented with the same words, but as visual speech and auditory speech. Shared neural representations of phonological structure of English words were found in each group in the superior and middle temporal cortex (STC/MTC) and these abstract representations were more similar across different language forms in better readers. Our data provide neurobiological evidence of the contribution of visual speech to abstract phonological representations of spoken language, that relate to reading proficiency, in both deaf and hearing adults. Significance Statement: Reading is an essential skill, yet some deaf children face reading challenges due to reduced access to signed or spoken language. In hearing children, successful reading depends on abstract phonological representations, but whether spoken language phonology relates to reading in deaf individuals remains unclear. Using fMRI and RSA, we show that deaf and hearing adults recruit neural representations of phonology that are shared by visual speech and other language forms (visual/auditory speech in hearing; visual speech/dynamic text in deaf) in the superior and middle temporal cortex. Critically, greater cross-modal alignment of neural representations of phonological structure was associated with better reading in both groups. These findings provide neurobiological evidence that visual speech contributes to phonological representations that relate to reading, regardless of hearing status.

This study examines how coordinated gaze and parent’s labelling during naturalistic play scaffold language development. Sixty-two, 15- to 18-month-olds (n = 28 female) and their mothers (n = 43 White) played for 15 minutes. Coordinated gaze was micro-coded and parents’ speech was transcribed. Children’s language skills were measured directly during the lab visit and via parent-report at 24 months. Results showed that frequency of parents’ ‘play monitoring’ – jointly looking to an object with their child and briefly looking to their object-focused child – positively predicted children’s language skills at 15- to 18- and 24 months. Referential labelling during children’s sustained attention to objects also predicted receptive language. These findings emphasise the importance of well-coordinated, child-sensitive parental behaviours in supporting toddlers’ emerging communication skills.

A bilingual’s highly variable early language learning demands may drive adaptations in social attention. For example, bilinguals show differences in face processing compared to monolinguals, automatically orienting more rapidly to faces and dwelling longer on faces and mouths than monolinguals. However, it is difficult to identify specific visual strategies from average-level data. This pre-registered study uses growth curve analysis within trials to explore individual differences in monolingual and bilingual children’s dynamic allocation of visual attention to faces and mouths in two age groups: seven- to 18-month-olds (n = 131 infants) and 18- to 34-month-olds (n = 745 toddlers). Results show that children’s attentional trajectories for viewing static faces and dynamic mouths is sensitive both to age and to children’s early language environments. Specifically, young bilinguals showed stronger systematic disengagement than monolinguals from faces and mouths after initial orientation. In contrast, older bilinguals prioritised the mouth more than monolinguals overall, driven by their steeper gradual increase in mouth-looking over stimulus time. Age-dependent shifts in attentional allocation over stimulus time were also evident, particularly in viewing of static faces. In infants, younger children showed earlier re-fixations to static faces than older children. In toddlers, attention to faces was more stable over stimulus time in older than younger children. Overall, the results suggest that age modulates the temporal structure of all children’s social attention from seven- to 34-months of age and are consistent with the hypothesis that bilinguals develop adaptive visual strategies to maximise their processing of social information.

Bilingual infants rely differently than monolinguals on facial information, such as lip patterns, to differentiate their native languages. This may explain, at least in part, why young monolinguals and bilinguals show differences in social attention. For example, in the first year, bilinguals attend faster and more often to static faces over non-faces than do monolinguals (Mercure et al., 2018). However, the developmental trajectories of these differences are unknown. In this pre-registered study, data were collected from 15- to 18-month-old monolinguals (English) and bilinguals (English and another language) to test whether group differences in face-looking behaviour persist into the second year. We predicted that bilinguals would orient more rapidly and more often to static faces than monolinguals. Results supported the first but not the second hypothesis. This suggests that, even into the second year of life, toddlers’ rapid visual orientation to static social stimuli is sensitive to early language experience.

Visual information conveyed by a speaking face aids speech perception. In addition, children's ability to comprehend visual‐only speech (speechreading ability) is related to phonological awareness and reading skills in both deaf and hearing children. We tested whether training speechreading would improve speechreading, phoneme blending, and reading ability in hearing children. Ninety‐two hearing 4‐ to 5‐year‐old children were randomised into two groups: business‐as‐usual controls, and an intervention group, who completed three weeks of computerised speechreading training. The intervention group showed greater improvements in speechreading than the control group at post‐test both immediately after training and 3 months later. This was the case for both trained and untrained words. There were no group effects on the phonological awareness or single‐word reading tasks, although those with the lowest phoneme blending scores did show greater improvements in blending as a result of training. The improvement in speechreading in hearing children following brief training is encouraging. The results are also important in suggesting a hypothesis for future investigation: that a focus on visual speech information may contribute to phonological skills, not only in deaf children but also in hearing children who are at risk of reading difficulties. A video abstract of this article can be viewed at https://www.youtube.com/watch?v=bBdpliGkbkY.